21469423 has 4 divisors (see below), whose sum is σ = 21677968. Its totient is φ = 21260880.

The previous prime is 21469421. The next prime is 21469429. The reversal of 21469423 is 32496412.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21469423 - 2¹ = 21469421 is a prime.

It is a super-2 number, since 2×21469423² = 921872247905858, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21469421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104118 + ... + 104323.

It is an arithmetic number, because the mean of its divisors is an integer number (5419492).

Almost surely, 2^21469423 is an apocalyptic number.

21469423 is a deficient number, since it is larger than the sum of its proper divisors (208545).

21469423 is a wasteful number, since it uses less digits than its factorization.

21469423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 208544.

The product of its digits is 10368, while the sum is 31.

The square root of 21469423 is about 4633.5108718983. The cubic root of 21469423 is about 277.9330057844.

The spelling of 21469423 in words is "twenty-one million, four hundred sixty-nine thousand, four hundred twenty-three".